Semiconductor devices are used in a variety of electronic applications, such as personal computers, cell phones, digital cameras, and other electronic equipment, as examples. Semiconductor devices are typically fabricated by sequentially depositing insulating or dielectric layers, conductive layers, and semiconductor layers of material over a semiconductor substrate, and patterning the various material layers using lithography to form circuit components and elements thereon.
Processing semiconductor wafers may lead to defects in the crystalline lattice of the semiconductor wafer. In some instances, voids, grain boundaries, interstitial defects, oxide-induced stacking faults, and other defects may be introduced during the fabrication process by imperfect substrate formation, layer deposition, etching, handling, impurities, and the like. Such defects may lead to degraded device performance.
Annealing is a process where a substrate is heated to a temperature to remediate crystalline damage. In some cases, the annealing energizes the atoms making up the crystalline structure to make new bonds with adjoining atoms, breaking high-energy bonds to form new, lower energy bonds. The annealing process may also comprise slowly bringing the heated wafer to a lower temperature in a controlled manner to avoid heat shock and prevent formation of new, undesirable crystalline defects.
Corresponding numerals and symbols in the different figures generally refer to corresponding parts unless otherwise indicated. The figures are drawn to illustrate the relevant aspects of the embodiments and are not necessarily drawn to scale.